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From: Dennis on 30 Jun 2008 18:41
I need another pair of eyes to look at this code. I am getting rows from
an OleDbDataReader from an Access 2002-2003 database.

...
If Not _reader Is Nothing Then
If _reader.HasRows Then
Dim _namePrefix As String = ""
Dim _ordinal As Int32
_ordinal = _reader.GetOrdinal("iNamePrefix")
If Not _reader.IsDBNull(_ordinal) Then
_namePrefix = _reader.GetString(_ordinal)
End If
...

The line "If Not _reader.IsDBNull(_ordinal) Then" is throwing an
InvalidOperationException (see below). The debugger says _ordinal is
correct (value is 1, which is as it should be - the 2nd column in the
SELECT * result set).

Any idea what I am doing wrong? It's probably something very simple that
I just can't see!

P.S. If it matters, the column in question is a Text column, length =
128, required = no, allow zero length = yes, default = "". I've tried
changing a few of these properties, but nothing seems to help.

TIA,

Dennis

***

System.InvalidOperationException was unhandled
Message="No data exists for the row/column."
Source="System.Data"
StackTrace:
at System.Data.OleDb.OleDbDataReader.DoValueCheck(Int32 ordinal)
at System.Data.OleDb.OleDbDataReader.IsDBNull(Int32 ordinal)
...
From: Dennis on 30 Jun 2008 19:21
Never mind. I new it was something dumb (like a missing _reader.Read).

Dennis

--

On Mon, 30 Jun 2008 18:41:33 -0400, Dennis <nobody(a)nowhere.com> wrote:

>I need another pair of eyes to look at this code. I am getting rows from
>an OleDbDataReader from an Access 2002-2003 database.
>
> ...
> If Not _reader Is Nothing Then
> If _reader.HasRows Then
> Dim _namePrefix As String = ""
> Dim _ordinal As Int32
> _ordinal = _reader.GetOrdinal("iNamePrefix")
> If Not _reader.IsDBNull(_ordinal) Then
> _namePrefix = _reader.GetString(_ordinal)
> End If
> ...
>
>The line "If Not _reader.IsDBNull(_ordinal) Then" is throwing an
>InvalidOperationException (see below). The debugger says _ordinal is
>correct (value is 1, which is as it should be - the 2nd column in the
>SELECT * result set).
>
>Any idea what I am doing wrong? It's probably something very simple that
>I just can't see!
>
>P.S. If it matters, the column in question is a Text column, length =
>128, required = no, allow zero length = yes, default = "". I've tried
>changing a few of these properties, but nothing seems to help.
>
>TIA,
>
>Dennis
>
>***
>
>System.InvalidOperationException was unhandled
> Message="No data exists for the row/column."
> Source="System.Data"
> StackTrace:
> at System.Data.OleDb.OleDbDataReader.DoValueCheck(Int32 ordinal)
> at System.Data.OleDb.OleDbDataReader.IsDBNull(Int32 ordinal)
> ...
From: sloan on 1 Jul 2008 14:09
Remember.

While _reader.Read()



End While

You could do an "if" instead of while, if you know its 1 row, but I don't
like to do that, just in case.




"Dennis" <nobody(a)nowhere.com> wrote in message
news:phqi64he1jgfkrral219493g8cau9ujsbm(a)4ax.com...
> Never mind. I new it was something dumb (like a missing _reader.Read).
>
> Dennis
>
> --
>
> On Mon, 30 Jun 2008 18:41:33 -0400, Dennis <nobody(a)nowhere.com> wrote:
>
>>I need another pair of eyes to look at this code. I am getting rows from
>>an OleDbDataReader from an Access 2002-2003 database.
>>
>> ...
>> If Not _reader Is Nothing Then
>> If _reader.HasRows Then
>> Dim _namePrefix As String = ""
>> Dim _ordinal As Int32
>> _ordinal = _reader.GetOrdinal("iNamePrefix")
>> If Not _reader.IsDBNull(_ordinal) Then
>> _namePrefix = _reader.GetString(_ordinal)
>> End If
>> ...
>>
>>The line "If Not _reader.IsDBNull(_ordinal) Then" is throwing an
>>InvalidOperationException (see below). The debugger says _ordinal is
>>correct (value is 1, which is as it should be - the 2nd column in the
>>SELECT * result set).
>>
>>Any idea what I am doing wrong? It's probably something very simple that
>>I just can't see!
>>
>>P.S. If it matters, the column in question is a Text column, length =
>>128, required = no, allow zero length = yes, default = "". I've tried
>>changing a few of these properties, but nothing seems to help.
>>
>>TIA,
>>
>>Dennis
>>
>>***
>>
>>System.InvalidOperationException was unhandled
>> Message="No data exists for the row/column."
>> Source="System.Data"
>> StackTrace:
>> at System.Data.OleDb.OleDbDataReader.DoValueCheck(Int32 ordinal)
>> at System.Data.OleDb.OleDbDataReader.IsDBNull(Int32 ordinal)
>> ...


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